Woven fabric



Oct. 24, 1961 KASEY' 3,005,472

WOVEN FABRIC Filed June 24, 1958 INVENTORS ROBERT ALLEN KASEY, JR.-EVERETT HARRIS RINKER, JR.

VERNAL HARDY SCHEUERMAN ATTORNEY 3,005,472 Patented Oct. 24, 1961 ice3,005,472 WUVEN FABRIC Robert Allen Kasey, in, Everett Harris Rinlter,In, and

Vernal Hardy fichenerrnan, Wilmington, Del, assign ors to E. I. du Pontde Nernonrs and Company, Wilmington, Del., a corporation of DelawareFiled June 24, 1958, Ser. No. 744,944 Stilaims. (Cl. 139426) Thisinvention relates to novel fabric construction and particularly wovensynthetic filament fabrics having improved covering power, durabilityand frictional properties.

It has been recognized for a long time that fabrics constructed ofsynthetic filament yarns have several deficiencies, in particular, lowfriction (characterized by slipperiness), low covering power, a Streaky,non-uniform appear-ance and a cold, clzunmy hand, which is mostcertainly uncomfortaole when in contact with the human skin. Some ofthese deficiencies may be minimized by the use of bulked yarns. However,fabrics constructed of 100% bulked continuous filament yarns often gotoo far in altering the filament fabric properties and introduce newproblems, such as excessive lint trapping, lower durability and greaterpiekiness.

An object of this invention is to provide a novel synthetic filamentwarp and fabrics made therefrom having improved properties, particularlysuitable for use as pillow cases, bed sheeting, shirtings, and the like.Another object of this invention is to provide woven synthetic filamentfabrics having increased friction without markedly affecting thestrength and durability of the fabric. Other objects will be apparentfrom the description given below.

These objects are accomplished by providing a woven fabric wherein thefilling yarn is composed of 100% substantially untwisted syntheticfilaments (except for producer twist) and the warp yarn is composed ofsynthetic filaments comprising 30% to 70% by weight or" a bulked yarnand 70% to 30% by weight of unbulked yarn. Both warp yarns may be eithertwisted or untwisted. The filling yarn will preferably be untwisted inorder to achieve maximum opacity in the final fabrics. The final fabricswill contain by weight 20%40% bulked filament yarn. Preferably, the warpwill comprise a bulked synthetic filament yarn wherein the filaments areindividually convoluted into coils, loops, and whorls at randomintervals along their lengths, said bulked yarn being disposed in thewarp alternately in single succession (i.e., end-and-end) with theremainder of the warp of unbulked filament yarn.

In the drawing, which illustrates a woven fabric of this invention andthe warp of yarns used therein,

FlGURE 1 is a simplified representation of a warp beam 1 having a numberof parallel yarns wound thereon consisting of alternate ends of unbulkedyarn 2 and bulked yarn 3 of twisted continuous synthetic organicfilament yarns in an end-and-end construction, and

FIGURE 2 is a plan View of fabric woven therefrom with a filling ofunbulked substantially untwisted continuous synthetic organic filamentyarn 4 as disclosed hereinafter. The fabric construction will be morereadily understood from the examples.

The novel warp construction of this invention may be composed of anytype of unbulked filament yarn alternating with any type of bulkedfilament yarn. Preterably, the alternation is in single succession inorder to achieve optically flat fabrics. For example, unbulked polyamidefilament yarn may be alternated with bulked polyamide filament yarn,polyester filament yam, acrylon-itrile polymer filament yarn, and thelike, and unbulked polyester filament yarn may be alternated with bulkedpolyamide filament yarn, polyester filament yarn, acrylonitrile polymerfilament yarn, and the like. The bulked yarn may be composed of a singlecomponent or multicomponents. For example, the bulked yarn may be 100%polyamide or a blend of polyamide and rayon, or a blend of polyester andrayon, preferably high tenacity rayon, or a blend of two or morepolyamide yarns of different lusters, etc. The bulked and unbulkedcomponents making up the warp may include continuous filament syntheticorganic yarns made from one or more fiber-forming materials, typicalexamples of which are cellulose acetate, cellulose triacetate,regenerated cellulose, polyamides such as polyhexamethylene adipamide,polyhexamethylene sebacamide, polycaproamide, and copolyamides,polyesters and copolyesters such as condensation products of ethyleneglycol with terephthalic acid, ethylene glycol with a /10 mixture ofterephthalic/isophthalic acids, ethylene glycol with a 98/2 mixture ofterephthalic/S-(sodium sulfo)isophtha11ic acids, andtrans-p-hexahydro-xylylene glycol with terephthalic acid,polyacrylonitrile, copolymers of acrylonitrile with other monomers suchas methyl acrylate or vinyl pyridine, polycarbonates, polyurethanes,polyesteramides, polyethylenes, polypropylenes, fluorinated ethylenepolymers and copolymers, and the like.

The novel warp construction of this invention has several advantagesindependent of its contribution to better fabric properties. These eudandcnd warps allow the preparation of a porous warp beam so that dyeingof the warp can be carried out directly on the beam. Lower yarn tensionscan be used successfully in beaming the bulked and unbulked filamentyarns together compared with the normally high tensions required forpreparing 100% unbulked filament warp beams. Warp yarns made up entirelyof unbulked filaments normally pack to give such a dense package thatthis construction is not susceptible to beam dyeing without poor dyeinguniformities. lso the end-and-end warps of this invention form a betterpackage, are easier to wind onto the beam, allow better beamingefficiency and uniformity and cause fewer defects than when handling awarp beam of 100% bulked yarn, because the ends of bulked yarn arespread farther. apart in the end-and-end iorm so that these ends avoidsnagging of the bulked yarns against one another. This also allowsbetter elficiency in weaving from the endand-end warp because of lesssnagging of ends during weaving than with 100% bulked warps. Larger warpbeams of this novel construction can be made than is possible with beamscomposed wholly of bulked yarns. Another advantage of these end-and-e'ndwarps lies in the greater latitude available to the manufacturer inbeing able to build a third dimension of aesthetic properties into awider variety of fabric types from variations in denier and degree ofbulkiness in the warp components, compared to only one type of fabricavailable from a warp beam of 3 end-and-end construction onto a beam, orthe two yarn types may be combined in the desired end-and-endrelationship into a warp sheet which is then slashed and wound onto abeam.

The degree of bulk, which is regulated by the percent overfeed of theyarn fed through a jet of turbulent fluid, in the bulked yarn componentused in preparing the novel warps of this invention will vary with theend use and properties desired in the fabrics. It is preferred to usebulked yarns having 5% to overfeed for best sheeting and pillow casefabric properties, although overfeeds from 2% to 30% or higher may beemployed in the bulked yarns going into fabrics for other end uses.

The filling yarns may be composed of one, two, or more continuousfilamentary materials, which may be of the same composition as any ofthose listed for the warp, or they may also be composed of silk orglass.

It may be desirable to construct fabrics from a warp composed of one ormore ends of bulked filament yarn alternating with two or more ends ofunbulked filament yarn. This technique can produce a distinct ribbedeffect which is desirable for use in certain types of fabrics.

The advantages of the novel fabrics of this invention over those having100% unbulked filament yarn in both warp and filling, which are of moreconventional construction, include higher coefficient of friction,reduced intensity and length of warp streaks, reduced filling barr,greater covering power (both reflected light and transmitted light),less fabric shiftiness (i.e., lower yarn slippage), more desirableluster and a better fabric handle and comfort. As compared with fabricswoven from 100% bulked yarn in both warp and filling, the end-andendconstructed fabrics of this invention include the advantages of loweramount of lint trapping, better weavability, better durability, reducedpickiness, i.e., less fabric snagging), lower cost, and possibility ofgreater variation in fabric stiffness without change in surfacecharacteristics. Surprisingly, the novel fabrics of this invention evenshow superiority over fabrics woven from 100% unbulked filament yarn inthe warp and 100% bulked yarn in the filling with respect to bettercovering power, better durability to repeated laundering, fewer reedmarks, and less filling yarn junctions which show up as non-uniformitiesafter dyeing. In addition, the end-andend constructed warps are easierto weave than 100% bulked warps, and the resulting fabrics of thisinvention have better durabiltiy than those made from 100% bulked warpand 100% unbulked filling.

It has also been found that improvements in fabric appearance may beobtained by using warp yarns with a different luster than the fillingyarns. In the fabrics of this invention, for example, using a dullfilling yarn with both components of the warp being semi-dull yarnsgives a pleasing three-dimensional type luster, compared with a chalkyappearance in an all dull fabric, and an undesirable sheen or glaze in afabric composed of all semi-dull yarns. This variation of luster betweenyarns is particularly useful for making satisfactory appearing shirtingfabrics. Further improvements in fabric properties (e.g., varyingdegrees of fabric crispness) may be achieved by variations in the denierof the unbulked filament yarn component of the warp and/ or filling.

It may be desirable in the construction of fabrics for certain specificuses to employ bulked yarn in the filling. This modification is usefulwhen a higher degree of friction is desired than is possible wtih 100%unbulked yarn in the filling, and it is also useful to help prevent yarnslippage in very lightweight fabrics. However, these advantages may beoutweighed for this modification of fabric, particularly when using 100%bulked yarn in filling, by the lower covering power and lowerdurability. A similar disadvantage occurs when fabrics contain spunyarns or staple fibers in any of the components of construction becauseof the high pilling propensity of these staple components. The fabricsof this invention do not contain any staple components in theirconstruction.

The bulked yarn suitable for use in the warp in the proportions statedmay be prepared by any convenient method which results in a yarncomprising a plurality of substantially continuous filaments which areindividually convoluted into coils, whorls, and loops at randomintervals along their lengths. Preferably, the bulked yarn possesses amultitude of ring-like loops irregularly spaced along the yarn surface.Such bulked yarns which are suitable for use in this invention may beprepared ac cording to the methods described by A. L. Breen in US.Patent 2,783,609 and in US. application Serial No. 375,- 372, filedAugust 20, 1953, by A. L. Breen and now Patent No. 2,852,906 datedSeptember 23, 1958. However, any similar bulked yarn made by othermethods may likewise be used as part of the warp in this invention,particularly that described in US. application Serial No. 698,103, filedNovember 22, 1957, by A. L. Breen and H. G. Lauterbach.

The novel end-and-end fabrics of this invention, which may be eitherwoven or warp knit, have many important uses, such as in the form of bedsheeting, pillow cases, shirtings, comforter fabrics, blouse fabrics,dresses, lingerie, suits, upholstery, filter fabrics, and the like.

The following examples illustrate specific embodiments of this inventionwithout intending to limit the same. The examples are chosen toillustrate specific advantages of the fabrics of this invention,constructed as shown in FIG. 2, over fabrics of more conventionalconstruction. All of the yarn components listed in the examples areeither bulked or unbulked continuous filament yarns and the per cent ofbulked yarn by weight is shown based on the warp and/ or total fabric.Each of the end-and-end constructed warps is formed of one end of theindicated bulked yarn alternating in single succession with one end ofthe indicated unbulked yarn. All nylon fabrics in the examples are wovenfrom polyhexamethylene adipamide yarns constructed as follows: All ofthe 100% unbulked fabrics have a warp reeded 104 ends per inch and afilling with a pick gear of 72 picks per inch. All end-and-endconstructed fabrics have a warp reeded ends per inch and a pick gear of72 picks per inch. All of the fabrics with bulked yarn in the fillingalso have a loom construction of 90 end/inch and 72 pick/inch. Thefinished fabric weight in each case is approximately 1.9 to 2.0 oz./sq.yd. The bulked yarns are designated in each case by the symbol T; forexample, 88T/ 80 meaning 88 denier bulked yarn made by bulking 80 denierunbulked yarn. These bulked yarns are made according to US. 2,783,609,referred to above, for example, in the case of 88T/ 80 yarn an overfeedof EXAMPLE 1 Coefitcient of friction Filament fabrics are known fortheir smooth continuous surface which is undesirable or unacceptable formany end uses. An excellent example of this is the fact that wovenfilament nylon bed sheetings are not satisfactory because of theslipperiness of the sheeting fabric against the blankets, top sheet, andpillow case. Only 25% to 35% bulked yarn (by weight of total fabric) inthe end-and-end construction gives suificient friction to produce asatisfactory sheeting product. The fact that such a small amount ofbulked yarn gives satisfactory friction was unexpected and very usefulas indicated later in the comparison of the end-and-end technology vs.use of bulked yarns in more conventional constructions. Table I givesrelative coefficients of friction for 100% unbulked filament fabric vs.fabric having end-and-end bulked/unbulked filament in the warp.

A spectrum of friction values can be obtained by varying the degree ofbulking (e. g., between 1% and 30% overfeed) in the bulked yarncomponent.

TABLE I Ooeflicient of Friction l 1 As measured under 163 g. normalforce at 45 angle of inclination.

EXAMPLE 2 Uniformity of appearance and streak level Filament fabricshaving 100% unbulked yarn in both warp and fill, especially those madefrom bright or semidull yarns, are characterized by severe streakiness.This streakiness manifests itself in the warp as long continuous streakswith both high intensity and frequency. In the filling non-uniformitiesappear as regular patterns which have been associated with draw-twisterpirn taper. The warp streaks in these fabrics are mostly caused byvariations in surface configuration rather than differences in inherentproperties of the yarns themselves.

Surprisingly, when the end-and-end technology of this invention is used,both the filling barr and warp streakiness are dramatically reduced. Thereduction in filling barr is completely unexpected and not entirelyunderstood. This result is important because it means that redrawing,lagging, and other operations that mills normally use to minimizefilling barr can be eliminated.

The end-and-end fabrics also show a surprising degree of warmuniformity. There are some warp streaks but these are discontinuous and,therefore, less objectionable than the long continuous streaks normallyassociated with filament fabrics. Improvements. in nylon fabricuniformity are indicated by data shown in Table II. All yarns used aresemi-dull yarns.

Reduction in fabric streakiness is a major problem limiting the use offilament fabrics in outer apparel enduses. With this new information,fabrics can be produced which not only have improved appearance, butalso have a range of hands varying from filamentous to fine spunlikedepending on the amount of bulk imparted to the yarn. These fabrics haveutility in apparel fabrics both where a uniform appearance and where achange from the Percent people judging the over-all uniformity ofendand-end to be superior to that of unbulked control (average of 20ratings).

Frequency measured as streaks/inch on Streakmeter. Intensity is ameasure of magnitude of streak level obtained from Streakmeterevaluation.

6 EXAMPLE 3 Use of the end-and-end technology gives greater transmittedlight-covering power than either bulked yarn in the filling or 100%unbulked yarn in both warp and filling for fabrics of equivalent weight.Improved covering power is a desirable property in many fabric typessuch as shirtings, sheetings, and blouses. Supporting data are shown inTable III, and all yarns used are dull yarns. It should be noted thatintroduction of 49% bulked yarn in a fabric does not significantlyimprove the covering power, whereas using only 29% bulked yarn in thefabric in the specific warp construction according to this inventiondoubles the covering power of the fabric even though it is a lighterweight fabric.

TABLE III Percent Bulked Yarn In Fabric Fabric t Weight (percent) FabricDescription (oz yd?) (1) Unbulked Warp and Fill:

703i7Z Nylon (2) Unbnlked Warp; Bulked Filling:

Warp70347Z Nylon Filling-WT 70-34-13Z Nylon (3) EndanCLEnd ConstructionWarp77T/7034l3Z Nylon, 70-

34-7Z Nylon (52% bulked in warp) Fllling7034l/2Z Nylon One of theproblems in 100% unbulked filament fabrics is fabric shiftiness or yarnslippage in the fabric. When unbulked fabrics are made in lowconstructions, the warp yarns or filling yarns may slip under externalstress and give fabric distortion. resin-treat low construction unbulkedfabrics to get away from this problem. Resin treatment brings aboutundesirable fabric stiffening and sometimes affects fabric performance.The end-and-end modification of this invention permits design of fabricswith lower constructions which are acceptable from the standpoint offabric shiftiness. Data to show this improvement are given in Table IV.This is important because it allows the construction of a sheetingfabric which is lighter in weight than 100% unbulked filament sheetingand, therefore, has more favorable economics. Lighter weight is alsoimportant in some apaprel end-uses from the standpoint of desirableaesthetics.

TABLE IV Fabric Weight (oz. yd?) Four lb. Displace- Fabrio Descriptionment in Mils 1 Warp Fill (1) Unbulkcd Warp and Fill:

70-34-7Z Nylon (2) End-and-End Construction:

Warp88T/8068l3Z Nylon, 70-

34-1/2Z Nylon (56% bulked in warp; 32% in fabric). Fill70341/2Z Nylon 1Amount of yarn slippage in mils under 4 lb. load.

EXAMPLE 5 It is often necessary tounder the loops in the bulked yarngives objectionable appearance and is difiicult to remove. Lint trappingis a function of the number and size of the loops on the bulked yarn.The reduced concentration of bulked yarn in the end-and-endconstruction, therefore, gives less lint trapping. Data comparing linttrapping propensity of fabric of 100% bulked polyester vs. end-and-endbulked/ unbulked polyester construction are given in Table V. The 100%bulked polyester fabric is loomed at 96 ends/inch and 68 picks/inch witha finished fabric weight of 2.55 oz./ sq. yd. The end-and-endconstructed fabric is loomed at 128 ends/inch and 68 picks/inch with thesame weight of finished fabric.

TABLE V Lint Trapping Fabric Description (Rating (1) 100% Bulked Warpand Fill:

1 Rating:

1No lint trapping visible. 2Noticeab1e amount of lint trapping.3-Objectionable amount of lint trapping. ft-Completely unacceptable.

EXAMPLE 6 Fabric durability Light weight filament fabrics constructed of100% bulked yarn in the filling can develop objectionable surfacedistortion under conditions of repeated use and laundering. Data inTable VI show that comparable Weight fabrics of end-and-end constructionhave superior durability. This is an important consideration in fabrictypes such as bed sheetings which must be durable. Often the appearancechange is accompanied by an undesirable change in fabric handle whichmakes the bulked filling construction even less attractive. Betterdurability is one of the most important reasons for superiority ofproperties of the end-and-end construction in bed sheeting fabrics.

TABLE VI Eflect of end-and-end construction on appearance change due torepeated laundering 1 383 5 yisible change in fabric surface.

2Noticeablc change in fabric surface (i.e., some fuzziness but stillacceptable).

3Objectionable change in appearance of fabric surface (i.e., pillformation and fabric distortion).

The claimed invention:

1. A woven fabric of improved covering power to transmitted light,durability to repeated laundering and uniformity of appearance, having awarp consisting of alternate ends of bulked and unbulked twistedcontinuous synthetic organic filament yarns and a filling consisting ofunbulked substantially untwisted continuous synthetic organic filamentyarn, said bulked warp yarn being of a denier 5% to 10% greater than thedenier of the unbulked yarn from which it is prepared.

2. A fabric as defined in claim 1 wherein the synthetic organicfilaments are nylon.

3. A fabric as defined in claim 1 wherein the synthetic organicfilaments are polyester.

References Cited in the file of this patent UNITED STATES PATENTS308,526 Simon Nov. 25, 1884 1,867,019 Meyer July 12, 1932 2,171,626Dreyfus et al. Sept. 5, 1939 2,595,778 Duckoff May 6, 1952 2,619,705Foster Dec. 2, 1952 2,738,176 Hargenrater Mar. 13, 1956 2,783,609 BreenMar. 5, 1957 2,789,340 Cresswell Apr. 23, 1957

1. A WOVEN FABRIC OF IMPROVED COVERING POWER TO TRANSMITTED LIGHT,DURABILITY TO REPEATED LAUNDERING AND UNIFORMITY OF APPEARANCE, HAVING AWARP CONSISTING OF ALTERNATE ENDS OF BULKED AND UNBULKED TWISTEDCONTINUOUS SYNTHETIC ORGANIC FILAMENT YARNS AND A FILLING CONSISTING OFUNBULKED SUBSTANTIALLY UNTWISTED CONTINUOUS SYNTHETIC ORGANIC FILAMENTYARN, SAID BULKED WARP YARN BEING OF A DENIER 5% TO 10% GREATER THAN THEDENIER OF THE UNBULKED YARN FROM WHICH IT IS PREPARED.